Cell Journal (Yakhteh)

246-253

Authors: Gholamhassan Haddadi , Alireza Shirazi , Zargham Sepehrizadeh , Seied Rabie Mahdavi , Maryam Haddadi

Objective: It has been suggested that the vascular endothelial growth factor (VEGF) gene expression plays an important role in radiation-induced injury to the spinal cord. This study assesses the radioprotective effects of N-acetyl-5-methoxytryptamine (melatonin) through its modulation of VEGF expression after localized irradiation of the cervical spinal cord. Materials and Methods: In this experimental study, we divided 192 male rats into four groups: 1. control (n=48); 2. rats that received an intraperitoneal (IP) injection of melatonin (n=48); 3. rats that received an IP injection of melatonin 30 minutes prior to cervical spinal cord gamma irradiation [dose: 22 Gy; (n=48)]; and 4. rats that received an IP injection of vehicle prior to spinal cord irradiation (n=48). The changes in VEGF expression were assessed using real-time RT-PCR and enzyme-linked immunosorbent assays. Samples for light microscopy were stained with hematoxylin and eosin (H&E). The differences among the groups were analyzed using the analysis of variance (ANOVA) test followed by Tukey’s multiple comparisons test. Results: Up-regulation of VEGF expression was observed from 8 to 22 weeks after irradiation (p<0.05). Paralysis and other radiation-induced myelopathy manifestations developed within 22 weeks after irradiation. VEGF expression in the melatonin pre-treatment group significantly down-regulated in the 20th and 22nd weeks after irradiation compared to the radiation-only group. Conclusion: The results support the hypothesis that modulation of VEGF expression by melatonin administration may increase the survival rate of irradiated animals.

264-269

Authors: Mohammad Hadi Sekhavati , Mojtaba Tahmoorespur , Kamran Ghaedi , Kianoush Dormiani , Mohammad Reza Nassiri , Yahya Khazaie , Mahboubeh Foruzanfar , Morteza Hosseini , Mohammad Hossein Nasr Esfahani

Objective: The aim of present study was cloning and expression of phiC31 integrase cDNA in a bacterial expression vector. Thus, an intra molecular assay vector was applied to show in vitro activity of recombinant protein. Materials and Methods: In this experimental study, phiC31 cDNA was subcloned into a prokaryotic expression vector and transformed into E.coli Bl21 (DE3). Recombinant phiC31 integrase was purified form the bacterial cell lysates and its activity was verified by an in vitro functional assessment. Results: Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the purifi ed phiC31 integrase confirmed the size of protein (70 kDa). Finally, the functionality of purified phiC31 integrase was verified. Conclusion: The results of this study indicated that the purified integrase has a great potential application for in vitro site-specific integration.

276-281

Authors: Mohammad Vahedi , Hossein Malekzadeh , Habib Haybar , Ali Reza Soltanian , Shermin Abdollahzadeh , Hojjat Yoosefi , Masoud Seyedian , Leila Yazdanpanah , Saeid Abrotan , Maryam Shabanpour Fooladi , Marziyeh Ghasemi

Objective: This study defines the relationship between salivary beta-2 microglobulin (ß2-M) and intensity of uremia in male patients diagnosed with chronic renal failure (CRF). Materials and Methods: In total of 42 males were enrolled in a case-control study. There were 21 cases of CRF and 21 control cases. We collected 10cc of saliva plus 5 cc of blood from all patients to determine ß2-M, blood urea nitrogen (BUN) and creatinine (Cr) levels. Results: There was a correlation between the level of serum BUN and salivary urea in controls and patients, which was statistically significant for controls (p=0.028).The correlation between serum and salivary Cr was 0.195 in controls (p=0.398) and 0.598 in patients (p=0.006), which was statistically significant in patients. The correlation between serum and saliva was 0.133 (p=0.566) in controls and 0.078 (p=0.737) in patients, which was not statistically significant. The correlation between serum BUN and ß2-M was 0.168 (p=0.469) in the control group and 0.629 (p=0.002) in patients, which was statistically significant in patients. The correlation between serum Cr and ß2-M was 0.110 (p=0.635) in the control group and 0.678 (p=0.001) in patients, which was statistically significant in patients. The correlation between serum BUN and salivary ß2-M was 0.093 (p=0.0690) in controls and 0.152 (p=0.152) in patients, which was not statistically significant. The correlation between serum Cr and salivary ß2-M was 0.072 (p=0.070) in the control group and 0.286 (p=0.209) in patients, which was not statistically significant in either group. Conclusion: The results of the study indicated that salivary ß2-M cannot be used as a noninvasive indicator to detect the severity of renal failure.

294-297

Authors: Alireza Shirazi , Ehsan Mihandoost , Ghazale Ghobadi , Mehran Mohseni , Mahmoud Ghazi-khansari

Objective: Ionizing radiation interacts with biological systems to induce excessive fluxes of free radicals that attack various cellular components. Melatonin has been shown to be a direct free radical scavenger and indirect antioxidant via its stimulatory actions on the antioxidant system.The aim of this study was to evaluate the antioxidant role of melatonin against radiation-induced oxidative injury to the rat liver after whole body irradiation. Materials and Methods: In this experimental study,thirty-two rats were divided into four groups. Group 1 was the control group, group 2 only received melatonin (30 mg/kg on the first day and 30 mg/kg on the following days), group 3 only received whole body gamma irradiation of 10 Gy, and group 4 received 30 mg/kg melatonin 30 minutes prior to radiation plus whole body irradiation of 10 Gy plus 30 mg/kg melatonin daily through intraperitoneal (IP) injection for three days after irradiation. Three days after irradiation, all rats were sacrificed and their livers were excised to measure the biochemical parameters malondialdehyde (MDA) and glutathione (GSH). Each data point represents mean ± standard error on the mean (SEM) of at least eight animals per group. A one-way analysis of variance (ANOVA) was performed to compare different groups, followed by Tukey’s multiple comparison tests (p<0.05). Results: The results demonstrated that whole body irradiation induced liver tissue damage by increasing MDA levels and decreasing GSH levels. Hepatic MDA levels in irradiated rats that were treated with melatonin (30 mg/kg) were significantly decreased, while GSH levels were significantly increased, when compared to either of the control groups or the melatonin only group. Conclusion: The data suggest that administration of melatonin before and after irradiation may reduce liver damage caused by gamma irradiation.

306-313

Authors: Abdolreza Rastegarnia , Abdolhossein Shahverdi , Tohid Rezaei Topraggaleh , Bita Ebrahimi , Vahid Shafipour

Objective: The aim of the present study was to evaluate three thawing rates on the post thaw motility, viability and chromatin structure of buffalo semen frozen in 0.5-ml straws. Materials and Methods: In this experimental study semen was collected with artificial vagina (42˚C) from four buffalo bulls.Split pooled ejaculates (n=4) were extended at 37˚C with a Bioxcell® extender. Semen was cooled to 4˚C within 2 hours, equilibrated at 4˚C for 4 hours, then filled in 0.5 ml French straws, and frozen in programmable cell freezer before plunging into liquid nitrogen. Straws were thawed at water bath temperatures of 37, 50 or 70˚C for 30, 15 and 6 seconds, respectively. Semen was incubated at 37˚C for 2 hours and evaluated for post thaw motility, viability, acrosomal and DNA integrity of spermatozoa. Analysis of variance (ANOVA) was used for comparisons of means. When the ANOVA test showed statistical differences, the mean of the treatments were compared using Duncan’s multiple range tests. Results: The initial postthaw motility (0 hour) averaged 62.7 ± 7.2%, 73.1 ± 9.77%, and 74.9 ± 8.58% for the three thaw rates, respectively. Kinematic parameters such as average path velocity, linearity and beat/cross frequency in the thaw rate of 70˚C for 6 seconds were superior to other rates studied (p<0.05). After 2 hours of incubation, proportions of progressive motility and Kinematic parameters decreased in all groups (p>0.05). A positive correlation was detected between sperm motility and thawing rate after two hours incubation times. The percentage of viable spermatozoa and spermatozoa with an intact acrosome and plasma membrane integrity were not different between the groups of samples thawed at different temperatures (p>0.05). The percentage of spermatozoa with chromatin dispersion forthe thaw rate of 70˚C for 6 seconds was significantly higher than for the to other rates studied (p< 0.05). In contrast with motility and viability, the DNA integrity of post thaw spermatozoa remained unaffected during 2 hours incubation. Conclusion: The post thaw motility and kinematic parameters of buffalo spermatozoa were significantly improved immediately after thawing by increasing the thawing rate from 37˚C in 30 seconds to70˚C in 6 seconds. However, this relative advantage had disappeared after incubation in a water bath at 37˚C for two hours.A thaw rate of 70˚C for 6 seconds was associated with higher chromatin dispersion than the other thaw rates studied. Sperm thawing over at 50 degrees could be safely used to improve motility recovery after sperm cryopreservation in buffalo bulls.